* Micrsoft RLE Video Decoder
* Copyright (C) 2003 the ffmpeg project
*
- * This library is free software; you can redistribute it and/or
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
typedef struct MsrleContext {
AVCodecContext *avctx;
AVFrame frame;
- AVFrame prev_frame;
unsigned char *buf;
int size;
} \
stream_byte = s->buf[stream_ptr++];
+static void msrle_decode_pal4(MsrleContext *s)
+{
+ int stream_ptr = 0;
+ unsigned char rle_code;
+ unsigned char extra_byte, odd_pixel;
+ unsigned char stream_byte;
+ int pixel_ptr = 0;
+ int row_dec = s->frame.linesize[0];
+ int row_ptr = (s->avctx->height - 1) * row_dec;
+ int frame_size = row_dec * s->avctx->height;
+ int i;
+
+ /* make the palette available */
+ memcpy(s->frame.data[1], s->avctx->palctrl->palette, AVPALETTE_SIZE);
+ if (s->avctx->palctrl->palette_changed) {
+ s->frame.palette_has_changed = 1;
+ s->avctx->palctrl->palette_changed = 0;
+ }
+
+ while (row_ptr >= 0) {
+ FETCH_NEXT_STREAM_BYTE();
+ rle_code = stream_byte;
+ if (rle_code == 0) {
+ /* fetch the next byte to see how to handle escape code */
+ FETCH_NEXT_STREAM_BYTE();
+ if (stream_byte == 0) {
+ /* line is done, goto the next one */
+ row_ptr -= row_dec;
+ pixel_ptr = 0;
+ } else if (stream_byte == 1) {
+ /* decode is done */
+ return;
+ } else if (stream_byte == 2) {
+ /* reposition frame decode coordinates */
+ FETCH_NEXT_STREAM_BYTE();
+ pixel_ptr += stream_byte;
+ FETCH_NEXT_STREAM_BYTE();
+ row_ptr -= stream_byte * row_dec;
+ } else {
+ // copy pixels from encoded stream
+ odd_pixel = stream_byte & 1;
+ rle_code = (stream_byte + 1) / 2;
+ extra_byte = rle_code & 0x01;
+ if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
+ (row_ptr < 0)) {
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (1)\n");
+ return;
+ }
+
+ for (i = 0; i < rle_code; i++) {
+ if (pixel_ptr >= s->avctx->width)
+ break;
+ FETCH_NEXT_STREAM_BYTE();
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte >> 4;
+ pixel_ptr++;
+ if (i + 1 == rle_code && odd_pixel)
+ break;
+ if (pixel_ptr >= s->avctx->width)
+ break;
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte & 0x0F;
+ pixel_ptr++;
+ }
+
+ // if the RLE code is odd, skip a byte in the stream
+ if (extra_byte)
+ stream_ptr++;
+ }
+ } else {
+ // decode a run of data
+ if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
+ (row_ptr < 0)) {
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (1)\n");
+ return;
+ }
+ FETCH_NEXT_STREAM_BYTE();
+ for (i = 0; i < rle_code; i++) {
+ if (pixel_ptr >= s->avctx->width)
+ break;
+ if ((i & 1) == 0)
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte >> 4;
+ else
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte & 0x0F;
+ pixel_ptr++;
+ }
+ }
+ }
+
+ /* one last sanity check on the way out */
+ if (stream_ptr < s->size)
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: ended frame decode with bytes left over (%d < %d)\n",
+ stream_ptr, s->size);
+}
+
+
+
static void msrle_decode_pal8(MsrleContext *s)
{
int stream_ptr = 0;
avctx->pix_fmt = PIX_FMT_PAL8;
avctx->has_b_frames = 0;
- s->frame.data[0] = s->prev_frame.data[0] = NULL;
+ s->frame.data[0] = NULL;
return 0;
}
s->size = buf_size;
s->frame.reference = 1;
- if (avctx->get_buffer(avctx, &s->frame)) {
- av_log(avctx, AV_LOG_ERROR, " MS RLE: get_buffer() failed\n");
+ s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
+ if (avctx->reget_buffer(avctx, &s->frame)) {
+ av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
return -1;
}
- if (s->prev_frame.data[0] && (s->frame.linesize[0] != s->prev_frame.linesize[0]))
- av_log(avctx, AV_LOG_ERROR, " MS RLE: Buffer linesize changed: current %u, previous %u.\n"
- " Expect wrong image and/or crash!\n",
- s->frame.linesize[0], s->prev_frame.linesize[0]);
-
- /* grossly inefficient, but...oh well */
- if (s->prev_frame.data[0] != NULL)
- memcpy(s->frame.data[0], s->prev_frame.data[0],
- s->frame.linesize[0] * s->avctx->height);
-
- msrle_decode_pal8(s);
-
- if (s->prev_frame.data[0])
- avctx->release_buffer(avctx, &s->prev_frame);
-
- /* shuffle frames */
- s->prev_frame = s->frame;
+ switch (avctx->bits_per_sample) {
+ case 8:
+ msrle_decode_pal8(s);
+ break;
+ case 4:
+ msrle_decode_pal4(s);
+ break;
+ default:
+ av_log(avctx, AV_LOG_ERROR, "Don't know how to decode depth %u.\n",
+ avctx->bits_per_sample);
+ }
*data_size = sizeof(AVFrame);
*(AVFrame*)data = s->frame;
MsrleContext *s = (MsrleContext *)avctx->priv_data;
/* release the last frame */
- if (s->prev_frame.data[0])
- avctx->release_buffer(avctx, &s->prev_frame);
+ if (s->frame.data[0])
+ avctx->release_buffer(avctx, &s->frame);
return 0;
}